2-p-nitro-or p-chlorobenzamido-acetohydroxamic acid

ABSTRACT

NOVEL BENZAMIDOACETOHYDROXAMIC ACIDS OF THE FORMULA:   1-R,4-(HO-NH-CO-CH2-NH-CO-)BENZENE   WHEREN R IS NITRO OR CHLORO ARE POTENT INHIBITORS OF UREASE. COMBINED WITH URINARY TRACT ANTIBACTERIALS AN IMPROVEMENT IN THE PREVENTION OF FORMATION OF URINARY CALCULI IN THE PRESENCE OF UREA SPLITTING ORGANISMS IS OBSERVED.

Patent US. Cl. 424-229 1 Claim ABSTRACT OF THE DISCLOSURE Novel benzamidoacetohydroxamic acids of the formula:

R-Q-C oNncmo ONHOH wherein R is nitro or chloro are potent inhibitors of urease. Combined with urinary tract antibacterials an improvement in the prevention of formation of urinary calculi in the presence of urea splitting organisms is observed.

This is a division of application Ser. No. 144,322, filed May 17, 1971, now US. Pat. No. 3,728,380.

This invention is concerned with chemical compounds. More particularly it is concerned with compounds of the formula:

R-Q-CONHCECONHOH wherein R is nitro or chloro and their combination with urinary tract antibacterial agents.

The compounds of Formula I are potent urease inhibitors. They may be readily prepared according to this scheme:

R-Q-CONHCHgCOOCzHs Hmon RQ-CQNHCmCONHQH oimon wherein R is nitro or chloro. Exemplary of this scheme are the following:

EXAMPLE I 2-(p-nitrobenzamido) acetohydroxamic acid A solution of hydroxylamine hydrochloride (28 g. 0.4 mole) in methanol (145 ml.) was treated with a solution of KOH (37 g. 0.7 mole) in methanol (84 ml.). The resulting inorganic salt was removed and the filtrate treated with ethyl p-nitrohippurate (84 g. 0.3 mole). After stirring for 3 hours, a solid precipitated. The entire reaction mass was stirred in approximately 500 ml. of water. A white crystalline solid was separated by filtration and dried at 60 to 35 g. The filtrate was acidified with glacial acetic acid to pH 6, precipitating a white crystalline solid which was dried at 60 to 38 g. The two crops were combined with 15 g. from a similar run and recrystallized from methanol to give 69 g. (67% M.P. 160l.

Calcd. for C H N O C, 45.19; H, 3.79; N, 17.57. Found: C, 45.10; H, 3.80; N, 17.53.

EXAMPLE 2 2-(p-chlorobenzamido)acetohydroxamic acid Into a suspension of 209 g. (1.50 moles) of glycine ethyl ester hydrochloride in 1,200 ml. of dry benzene was slowly added 263 g. (1.50 moles) of p-chlorobenzoyl chloride. This mixture was heated under reflux for 22 3,787,569 Patented Jan. 22, 1974 hours, then filtered and the white precipitate was recrystallized from methanol giving 292 g. (82.5%) of ethyl 2-(p-chlorobenzamido)acetate, M.P. 114-117 C.

Analysis.Calcd. for C H NO Cl (241.67): C, 54.67; H, 5.01; N, 5.80. Found: C, 54.95; H, 4.97; N, 6.08.

To a stirred solution of 58 g. (0.83 mole) of hydroxylamine hydrochloride in 350 ml. of anhydrous methanol was added a solution of 70 g. of potassium hydroxide in 150 ml. of anhydrous methanol. A white salt immediately precipitated. This mixture was cooled in an ice bath and the salt was removed by filtration. The filtrate was placed into a 2 l. flask equipped with a stirrer, a thermometer and a drying tube. To the filtrate was added with stirring g. (0.42 mole) of ethyl 2-(p-chlorobenzamido)acetate which went into solution. Approximately 2 minutes later a thick white precipitate formed. The mixture was stirred at room temperature overnight. The potassium salt was collected by filtration and dried at 60 to 90 g.

A second run of the same size was made with 91 g. of the potassium salt being obtained. The two crops of salt were combined making a total of 181 g. which was placed in 2,000 ml. of cold water. Glacial acetic acid (40 ml.) was added to give a final pH of 5. The white precipitate was collected by filtration and dried to 160 g. in a 60 oven. The 160 g. of crude product was recrystallized from 4,800 ml. of methanol. After cooling the solution overnight in the refrigerator, the product precipitated as white crystals which were collected by filtration and dried at 60 C. to 121 g. (63.8% overall yield), M.P. 17l172 C.

The anti-urease activity of the compounds of this invention is exemplified below:

TABLE 1 [The inhibition of urease purified from Proteus mirabilis (Pr-91) and of grease clontained within intact cells of several species and strains 01 ro eus Concentration of inhibitor for 5 inhibition of urease Compound of Ex. 1 Compound of Ex. 2

Mole/liter ngJl. Mole/l. pg-ll.

Purified enzyme:

Proteus mirabills:

Pr-91 ..'..':.';:.i 5. 3X10' 128 2. 5X10 57 Intact cells:

Proteus mirabflis:

Pr-91 1. 1X1()- 264 3. 6X10- 82 Pr-104- 1. 3X10 310 4. 9X10- 112 Pr-- 7. 4X10- 178 3. 6X10- 82 Pr92 2. 2X10- 526 3. 9X10 89 Proteus vulgaris- 2. X 0 6 3- X 0 82 4. 0x10 96 a. 5x10- 80 Proteus morgnn:

Pr-94 1. 2X10- 286 2. 9X10 66 Pr-lOO 6. 2X10' 1, 458 1. 5X10" 342 Pr-lOl 7. 7X10- 184 3. 3X10- 75 The compounds of this invention are valuable adjuncts in the therapy of urinary tract infection caused by urea splitting bacteria such as Proteus mirabilis whereby urea is decomposed to ammonia with resultant formation of insoluble salts such as ammonium magnesium phosphate giving rise to calculi formation and obstruction posing a site of reinfection impairing the efiicacy of otherwise effective urinary tract antibacterials such as ampicillin, sulfamethoxazole and nitrofurantoin.

When the compounds of this invention are administered in conjunction with known antibacterial agents to rats in which Proteus mirabilis genitourinary tract infection has been induced, the appearance of calculi is diminished and sometimes prevented. Also, at times, dissolution of formed calculi is accomplished through this joint therapy.

The following table is illustrative of the beneficial result achieved through the concomitant therapy referred to above:

TABLE II hydroxamic acid to ampicillin and sulfamethoxazole is 2:1 and to nitrofurantoin 10:1.

dosages for 6 days beginning 24 hours after infection] Statistical significance of the difference between an Test for Mean mg. experimental poten- Rats phosphorus and the tiation 2 Dosage, per as calculi control Compound(s) mg./kg group per bladder group 1 EU AB None .50 5.4

12.5 10 1.9 .01 12.5 9 1.1 .05 2.5 9 2.2 .02 Compound of Example 25 10 3. 3 02 50 9 1.0 .01 Compound of Example 2. 25 8 3. 3 05 O Do a. .i }.E inf 28 7 2.3 .02

ompoun o ramp 0 plus sulfaxnethoxazole 12.5 9 Compound 01 Example 1. 25 9 0 6 01 plus suliamethoxazole 12.55

0 c d (E 1 2 122g} 9 M 0.1

ompoun o xamp e 0 plus srliakulgethoxalzole 12.5} 9

ompoun o xampe 50 0 plus t i g g f y 2g 10 0.3 .01 .01 .01

ompoun o xamp e C plus g g g l i 53 10 1.2 .01 10 10 ompoun o xamp e 0 plus i g l i 2g 9 01 .01 .01 .01

ompoun o xamp e 0 plus g i i 53 10 0.8 .01 .01 .01

ompoun o xampe 0 plus g g l 12 1o 01 .01 .01 .01

ompoun o xamp plus Ampieimn 5g 0.2 .10 .10 .10 22} 9 01 .01 .01 .01 plus Ampicimn" 12 5 10 0.1 .10 .01 .01

1 Statistical evaluation was by the Wilcoxon rank sum test [Wilcoxon et a1. "Some Rapid Approximate Statistical Procedures, Lederle Laboratories, 7-9 (1964)].

1 The number is the probability that the difierence in the mean mg. phosphorus as cystic calculi between rats receiving an antibacterial agent (AB) only or an urease inhibitor (EU) only on the one hand, and the mean mg. phosphorus as cystic calculi from rats receiving both (AB) and (E U) on the other, is a chance occurrence.

The compounds of this invention by themselves and in conjunction with ampicillin, sulfamethoxaz ole or nitrofurantoin are readily formulated in pharmaceutical dosage forms such as tablets, lozenges, suspensions, troches, and capsules using conventional pharmaceutical carriers and excipients with which there is no incompatibility.

What is claimed is:

1. A composition for treating urinary tract infection caused by urea splitting Proteus organisms consisting of the combination of 2-(p-chlorobenzarnido)acetohydroxamic acid and a member selected from the group consisting of ampicillin, sulfamethoxazole and nitrofurantoin in eiiective dosage amount in which the proportion of said References Cited JEROME D. GOLDBERG, Primary Examiner U.S. Cl. X.R. 424271, 324

W 3? 1 -UNITED'S'IIATESI PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 8,787,569 Dated Jargarv 22. 1974 'InVenwI-(S) Roland N. Johnson and J on A. Andersen It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

I'' Line 4: The name of the second inventor Jon "Anderson" should be .Ton A .*,--Andersen--.

Signed and sealed this lL th day of May l97 LL.

SEAL) .Attest:

I EDWARD M.FLETCHEH,J'R. v C. MARSHALL DANN Attesting Officer Commissioner of Patents 

